Reference is made to my copending application, Ser. No. 928,184, filed Nov. 7, 1986 on an in-tank fuel module. The disclosure in that application is that of a vertical reservoir in the form of a canister mounted upright in a portion of a vehicle fuel tank, there being an electric fuel pump in the canister which draws fuel from the bottom of the canister open to the general tank area. Overflow from the pump not used by the engine feeds back into the top of the canister through a return passage and is contained by a valve in a lower septum in the canister. The valve is usually closed but may be opened by the action of a mesh diaphragm. The diaphragm is such that it will pass fuel under normal circumstances. However, if a condition arises wherein the lower end of the canister is starved of fuel due to low fuel level and side sloshing, the diaphragm will be actuated since, due to the capillary action of the fuel, air will not readily pass the mesh diaphragm. Accordingly, the valve which retains the auxiliary fuel in the canister is opened and fuel is made accessible to the pump inlet to avoid stalling of the engine.
If for some reason the mesh diaphragm becomes clogged so that it will not pass fuel readily, the pump inlet would create a vacuum in the bottom of the canister, the valve 72 will open, and all of the reserve fuel in the canister would be drained. If this happens, the pump would start pumping air and this is an undesirable condition. The present invention has, as an object, the provision of a float valve which will close the canister volume when fuel in the canister is depleted. Thus, under most circumstances, the pump vacuum will clear the mesh diaphragm and restore normal operation of the stem.
Other objects and features of the invention will be apparent in the following description, accompanying drawings, and claims in which the invention is described together with details to enable persons skilled in the art to practice the invention, all in connection with the best mode presently contemplated for the invention.